Structure of a uniform thermal conductive heat dissipation device

ABSTRACT

An improved structure of a uniform thermal conductive heat dissipation device, having a thermal conductor and a plurality of heat pipes. The thermal conductor includes a convex body member, on which a plurality of parallel connecting parts is formed to allow the heat pipes embedded therein. Each of the heat pipes has a wick structure and a working fluid therein. Each heat pipe has a heat absorbing portion and a heat dissipation portion. The heat absorption portion is closely in contact with the thermal conductor. Thereby, each of the heat is subject to the same amount of heat to result in a uniform thermal conduction and dissipation effect.

BACKGROUND OF THE INVENTION

The present invention relates in general to an improved structure of auniform thermal conductive heat dissipation device, and more particular,to a heat dissipation device of which the heat pipes are embedded in thethermal conductor to result in uniform thermal conduction and heatdissipation.

In the old computer design, the operation speed of central processingunit (CPU) is so slow that an aluminum extrusion type or fin-type heatsink will be sufficient to dissipate the heat generated by the centralprocessing unit. However, as the clock of central processing unit hasexceeded 1 GHz or even reached 3 GHz, the heat generated by the centralprocessing unit increases proportionally to the operation speed.However, due to the limited space within the housing, the conventionalheat dissipation device can hardly provide effective heat dissipation.It has thus become a critical problem to be resolved in computerindustry.

FIG. 1 shows a conventional heat dissipation device. As shown, the heatdissipation device includes a thermal conductive plate 10 a, a pluralityof heat pipes 20 a and a heat sink 30 a. The thermal conductive plate 10a has a planar body member attached to a heat generating device such asa central processing unit. The top surface of the thermal conductiveplate 10 a is opened to form a plurality of parallel channels 11 aallowing the heat pipes 11 a to be embedded therein. Each of the heatpipes 11 a includes a wick structure and a work fluid therein. The topend of each heat pipe 11 a includes a heat dissipation portion, whilethe bottom end of each heat pipe 11 a includes a heat absorbing portionin abutting contact with the thermal conductor 10 a. The heatdissipation portion is in contact with the heat sink 30 a to form theheat dissipation device. Thereby, the heat generated by the heatdissipation device can be guided to the thermal conductive plate 10 a,and further dissipated from the heat sink 30 a via the heat pipes 20 a.

However, the conventional heat dissipation device as disclosed above hasthe following drawbacks. As the dimension of the heat generating devicesuch as the central processing unit shrinks, the heat generated therebyis very concentrated. Therefore, the heat pipes 20 a closest to the heatgenerating device can absorb the heat and vaporize the working fluidtherein instantly. Thereby, the heat can be conducted to the heatdissipation portion efficiently. However, as the heat sink 30 a cannotdissipate the heat away efficiently, such heat reflows back to the heatpipes 20 a. As a result, the work fluid cannot be condensed quick enoughto absorb further heat. The thermal conduction mechanism by phasetransition between liquid state and gas state of the heat pipes 20 a isthus degraded. Further, the heat pipes 20 a at two sides are relativelyremote to the heat generating device. Therefore, the propagation path ofheat is too long, and the heat pipes 20 cannot absorb the heatefficiently.

BRIEF SUMMARY OF THE INVENTION

The present invention provides an improved structure of a uniformthermal conductive heat dissipation device, of which heat pipes areembedded in a thermal conductor, and propagation path of heat has beenso arranged that the distance between the heat source and each heat pipeis the same. Therefore, a uniform thermal conduction and heatdissipation effect is obtained.

The uniform thermal conductive heat dissipation device provided by thepresent invention includes a thermal conductor and a plurality of heatpipes. The thermal conductor includes a convex member, on which aplurality of parallel connecting parts is formed. The heat pipes areembedded in the connecting parts. Each of the heat pipes includes a wickstructure and a working fluid therein. In addition, each of the heatpipes is partitioned into a heat absorbing portion and a heatdissipation portion. The heat absorbing portion is in abutting contactwith the thermal conductor.

These and other objectives of the present invention will become obviousto those of ordinary skill in the art after reading the followingdetailed description of preferred embodiments.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary, and are intended toprovide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

These, as well as other features of the present invention, will becomeapparent upon reference to the drawings wherein:

FIG. 1 shows a conventional heat dissipation device;

FIG. 2 shows an exploded view of a heat dissipation device provided in afirst embodiment of the present invention;

FIG. 3 shows a perspective view of the heat dissipation device as shownin FIG. 1;

FIG. 4 shows a cross sectional view of the heat dissipation device asshown in FIG. 1;

FIG. 5 shows a cross sectional view of a heat dissipation deviceprovided in a second embodiment of the present invention;

FIG. 6 shows a perspective view of a heat dissipation device provided ina third embodiment of the present invention; and

FIG. 7 shows a perspective view of a heat dissipation device provided ina fourth embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of thepresent invention, examples of which are illustrated in the accompanyingdrawings. Wherever possible, the same reference numbers are used in thedrawings and the description to refer to the same or like parts.

Referring to FIGS. 2-4, an exploded view, a perspective view, and across-sectional view of a first embodiment of a heat dissipation deviceare illustrated. The heat dissipation device includes a thermalconductor 10 and a plurality of heat pipes 20.

The thermal conductor 10 is fabricated from material with good thermalconductivity such as copper, for example. The thermal conductor 10includes a convex body member 11. The convex body member 11 has asemi-circular, trapezium (as shown in FIG. 5), or other geometric crosssection. In the current embodiment, the body member 11 has asemi-circular cross section. The curve surface of the body member 11 isprocessed to form a plurality of parallel connecting parts 12. Theconnecting parts 12 are in the form of elongate trenches or channels.

Each of the heat pipes 20 includes an elongate or U-shape circular tube,in which the wick structure and working fluid are introduced. By thethermal conductive mechanism of the wick structure and the gas-liquidphase transition of the working fluid, the generated heat can be quicklydissipated. The heat pipe 20 further includes a heat absorbing portion21 and a heat dissipation portion 22. The heat absorbing portion 21 isconformal to the connection portions 12 of the thermal conductor 10,such that an abutting contact can be obtained.

Therefore, the heat pipes 20 can be uniformly embedded in the curvedsurface of the thermal conductor 20. According to the heat propagationpath, the heat pipes 20 are subject to the same amount of heat to obtaina uniform heat dissipation effect.

The heat dissipation device may further comprise a heat sink 30 mountedto the heat pipes 20. The heat sink 30 may includes a stack of fins 31.The fins are fabricated from materials with good conductivity such asaluminum or copper. The bottom of the heat sink 30 is recessed to form areceiving window 32 conformal to the body member 11 of the thermalconductor 10. On the surface of the receiving window 32, a plurality ofconnecting structures 33 is formed to receive the heat dissipationportions 22 of the heat pipes 20.

Referring to FIGS. 6 and 7, third and fourth embodiments of the presentinvention are illustrated. As shown, the connection parts 12 thermalconductor 10 are in the form of elongate circular channels, and theconnecting structures 33 are also in the form of elongate circularchannels. Thereby, the heat absorbing portions 21 and heat dissipationportions 22 of the heat pipes can be connected thereto. The structure asdisclosed increase the contact area between the heat pipes 20, thethermal conductor 10 and the heat sink 30 (as shown in FIG. 6). Further,the surface area for heat dissipation of the heat sink 30 is alsoenlarged to enhance the overall heat dissipation efficiency.

Therefore, the present invention provides at least the followingadvantages.

1. The convex body member provides the heat propagation paths alongwhich the heat pipes are subject to the same amount of heat. As aresult, a uniform thermal conduction and heat dissipation effect isobtained.

2. The heat pipes have high thermal conduction with fast-responding andlow-resistant features, such that the heat can be guided and dissipatedaway instantly to prevent the computer from being down or operating atan abnormal temperature.

3. The heat pipes are embedded in the thermal conductor or the heatsink, such that the heat dissipation is enhanced.

This disclosure provides exemplary embodiments of the present invention.The scope of this disclosure is not limited by these exemplaryembodiments. Numerous variations, whether explicitly provided for by thespecification or implied by the specification, such as variations inshape, structure, dimension, type of material or manufacturing processmay be implemented by one of skill in the art in view of thisdisclosure.

1. A uniform thermal conductive heat dissipation device, comprising athermal conductor and a plurality of heat pipes, wherein the thermalconductor includes a convex body member and a plurality of connectionportions recessed from a convex surface of the body member, and each ofthe heat pipes includes a heat absorbing portion and a heat dissipationportion, the heat absorbing portion is embedded in the correspondingconnection portion
 2. The device of claim 1, wherein the thermalconductor is fabricated from copper.
 3. The device of claim 1, whereinthe thermal conductor includes a semi-cylindrical body member.
 4. Thedevice of claim 1, wherein the body member has a trapezium crosssection.
 5. The device of claim 1, wherein the connection portionsinclude a plurality of slots.
 6. The device of claim 1, wherein theconnection portions include a plurality of circular channel.
 7. Thedevice of claim 1, wherein the heat pipes include elongate tubes.
 8. Thedevice of claim 1, wherein the heat pipes include U-shape tubes.
 9. Thedevice of claim 1, further comprising a heat sink mounted to the heatpipes.
 10. The device of claim 9, wherein the bottom of the heat sink isrecessed to form a receiving window, and a plurality of connectionstructures are formed on the surface of the receiving window forreceiving the heat dissipation portions of the heat pipes.
 11. Thedevice of claim 10, wherein the connection structures comprisesemi-circular slots.
 12. The device of claim 9, wherein the connectionstructures are conformal to the heat dissipation portions of the heatpipes.
 13. The device of claim 12, wherein the connection portionsinclude circular channels.